This is a city in mourning once again, not even a year since "Charlie Hebdo." The mood here very quiet and subdued. These people coming together for unity and concern for their others, but also as a subtle act of defiance.

President Hollande, Hala, had said stay home if you can. But that's not what Parisians are about. This was an assault on the lifestyle from these murderers from actors of Islamism and these people show they will not have their lifestyle change.

HALA GORANI, CNN ANCHOR: And the lifestyle of people of all religions and all races as well. It's not so much a war on just one section of France. It's all French, all Parisians who enjoy a night out, who enjoy going to a good restaurant, who enjoy going to a football/soccer game, et cetera -- all those targets were carefully chosen to say -- by fanatics -- to say we do not agree with the way you live and we want to divide you.

But -- if I know one thing about Parisians, you don't tell them what to do. They're out and they're still be going out and they'll still be enjoying what makes them so, you know, intrinsically Parisian.

CUOMO: Now, while this is a painful reminder of what happened with "Charlie Hebdo", it also different in very material and important ways, in terms of the fight against Islamism and terror. We do have breaking news on a couple of fronts.

First, CNN has learned from a member of the French senate, that the first suicide bomber who -- a man who exploded himself at the French soccer stadium just outside Paris, he came to Europe as part of an organized group smuggled in with refugees. They landed on the Greek island of Leros a month ago, he was carrying a passport from Syrian origin, that was his stated country of origin, whether or not that was legit, we'll need more investigation. But that was given to him under these emergency provisions -- shining a light, Hala, on how you treat the refugees, how much you can know within their desperation, there is also opportunity for evil.

GORANI: And we have info on another attacker as well. He's named as a 29-year-old French citizen, homegrown terrorist, born in this country and interestingly -- or not surprisingly, I should say, with a petty criminal past. This is similar to the attackers in the "Charlie Hebdo" series of vicious attacks in January.

CUOMO: Now, who they are not important, who they knew who helped them critical in importance.

Another thing we're not giving you in agonizing detail is how many are dead. Why? Because we don't know. You should not be consumed with the numbers. You know the loss of humanity is very great here. There are so many fighting for their lives in the hospitals wounded that it is premature to get to the idea. The human loss is huge, and that is going to be an unqualified truth.

GORANI: We know it's a huge number. We also know from French authorities this morning, they're not all of the victims have been identified. One can only imagine the agony of family and friends still looking, you know, wondering, are they injured? Have they perished? Those questions still for a couple of dozen of victims' family and friends not answered this morning.

CUOMO: The biggest question, who else was involved and where else will this lead?

And, of course, with the G20 Summit happening now, the world's leadership getting together, what will happen next in response for the investigation?

Let's get to CNN international correspondent Clarissa Ward -- Clarissa.

Well, you talked a little bit about that French national who has been identified. Ismail Mostefai, 29 years old, had a history of crime but had never actually been to prison. But we do know that six people who are close to Mostefai are now being held, they're being interrogated. Police trying to find out who this young man was, who he was working with possibly.

And we also know that police found an abandoned getaway car, a black Seat. In that car, a number of Kalashnikovs or AK-47 rifles, it's not clear which attack that car was the getaway car for.

Essentially now, police really trying to lock down a number of leads, trying to work out if there are more attackers at large and who were the network that facilitated and helped to orchestrate this enormous attack, because it is a sophisticated and complex attack, unlike previous more lone wolf types of attacks that we've seen ISIS call for and carry out here in Europe.

One other thing I wanted to note, yesterday, we talked quite a lot about the passport of an Egyptian national that was found, people were speculating that one bombers might have been Egyptian.

CNN has actually managed to get in touch with the family of the holder of that Egyptian passport. He is, in fact, a victim of this vicious crime.

[08:05:03] He is now in intensive care. And it's not clear yet whether or not he will make it. But it gives you a sense of the fog and chaos following this kind of an event where everybody is trying to find leads in a very murky and very difficult and very depressing time.

CUOMO: And, Clarissa, as we're dealing with where we go from here investigatively, obviously, there seem to be two major points of concern, your take on them, please? One is that the men who came here in the name of Islamism are not the only ones involved in this plot. The other is the suicide vests a first for French to deal with, suicide bombers wearing vests, but that the chemical compound TATP very volatile, doesn't transport well, probably locally made.

What do these pieces mean to you?

WARD: Well, this is a really big concern. This is important for our viewers in the U.S., Chris, perhaps they don't understand, these kind of weapons, assault rifles, grenades, explosive, suicide, it's very difficult to get ahold of these weapons in Europe. There's very strict gun control here.

So, how did these men get ahold of these weapons? Where did they learn this expertise to build these exclusive vests? Where they train in Syria? Did they spend time there? Or are they working in conjunction with a nexus of a criminal enterprise perhaps?

We know that in the case of "Charlie Hebdo," there were strong criminal links. So, a lot o questions with potentially devastating impact for France, as they try to explore this nexus on the one hand criminal elements who know how to dodge police, who know how to get weapons, who know how to get explosives and also radicalized elements, who have been so brutalized and dehumanized by the violence they experienced and participated in Syria and now coming back, organized, well armed and ready to kill.

CUOMO: All right. Clarissa, thank you very much. Please keep us in the loop on whatever you learn. The investigation is very robust and expanding all the time.

GORANI: All right. Let's bring in our chief international correspondent, Christiane Amanpour. She joins us now with new information about the attack that occurred at the Stade de France football stadium.

CHRISTIANE AMANPOUR, CNN CHIEF INTERNATIONAL CORRESPONDENT: That's right. As we've been reporting this morning, there are really dramatic new information, not just in the investigation, but in what it means in the new threat to certainly Europe as we've seen in France, and that is that they are now convinced -- the French authorities are now convince that these people who blew themselves up at the Stade de France, at least one of them, maybe all three, are part of what they call an organized crime gang of terrorists who come in posing as migrants and refugees, thus, you know, fulfilling the threat by ISIS publicly several weeks ago we will send off ISIS with these waves of migrants to fight you in your own homes.

Don't think that you're safe even in your own homes and that has been proven here Friday the 13th here in France, a completely different type of attack of terrorist attacks for France, in fact for anyone. That this particular individual who blew himself up first at the French stadium where the football match was interrupted by these explosions was in possession of what was a false possible but a possible that was given under these new emergency provisions as they do for migrants now.

He had come along with a boatful of people to Leros in Greece. The date October the 3rd, given a new passport, Syrian passport.

His name was Ahmed Abu Mohammad. That's the game he gave. They're sure that is a false name, born in September of 1990. September 10th of 1990, went on, like all the people who go from Greece through the Balkans and on into western Europe, Macedonia, Serbia, Croatia, where he was registered as a refugee at one of the main refugee camps on the 7th of October.

And they said that, you know, they figured this all out because the passport and this finger that was left after he blew himself up, the print matched the passport but it didn't match the French database, therefore they didn't know him and they said that's why they are convinced he's part of this migrant wave.

So, it's a very dramatic development not just for the criminal and terrorist investigation but for what it means politically to Europe struggling with this immigration, not just the hordes and the overwhelming number of refugees coming but what it might mean in terms of security.

GORANI: And also, your source was telling you about the two other suicide bombers who they say were carrying other fake passports?

AMANPOUR: That's right. Again, this was confirmed by the interior ministry here. That the other two, we're told, were carrying false Turkish passports and emphasized the word false. I don't yet have the names of those people.

But false Turkish passports paints this large picture of what was described the French senator who told to me this, having been briefed by the interior ministry, that this is the first manifestation of what they call this new squad of terrorists that are coming in, at least this one, with the immigrants.

[08:10:17] CUOMO: It's interesting to hear the reaction of the intelligence community here in France and also the United States. What do we see here so far?

There's speculation that at least some of the attackers were young. They see it in their inexperience, thank God, of how they use their own vests more people weren't taken. In almost all the instances they exploded themselves and ended up not killing anybody else. But their youth speaks to the poison of Islamism and how these people can be turned very quickly through the use of that misshapen idea of what it is to be a Muslim.

But on the other side, they're saying from the U.S. side of intelligence, France has all the ingredients of the difficulty in this war, shared borders, not under the conditions that are now a state of emergency in ordinary life, not having the heightened sense of purpose that they may share in other places like the United States, a huge native population now, maybe some 5,000, who are potentially targets of radicalism and Islamism. And their ability to get weapons here just like anywhere else, that this is a place of not if but when we see attacks like this.

AMANPOUR: Well, it happened and when was on Friday and you can imagine in Britain they're worried. The head of MI-5, domestic intelligence, you know, said over the last two months that we are really seeing the biggest level of threat we've ever seen in regard to ISIS.

CUOMO: The U.S., too, it's a big part of the presidential election, a big part of the immigration prospect. I mean, this is really harsh music to people's ears there.

AMANPOUR: It is, but I think people have to be incredibly lucid about what this is.

The original fears voiced by police commissioners from New York to elsewhere, FBI, also national security and law enforcement officials in the United States including in Europe was about blowback from Syria. Their fears started a couple years ago.

The blowback from Syria and then the blowback from ISIS, you know, not extinction wishing this flaming war in Syria is what has, in inexorable logic scorned this, right? It's in a state of vacuum and who has taken the vacuum? ISIS. That's the bottom line.

(CROSSTALK)

CUOMO: Reasonable basic that doesn't mean it doesn't represent a threat that you're going to have to deal with. In the U.S. right now, the dialogue instead of 65,000, 85,000 refugees to be brought in, how can you effectively vet something like this?

GORANI: And put it in context in terms of numbers as well, we're talking 400,000 refugees here.

AMANPOUR: The biggest threat, let's find out who this guy was. The biggest -- a false passport, remember. The biggest threat, according to law enforcement, of course this new wave coming in potentially as organized groups, but all the hundreds and thousands gone from the United States, France, Britain, Belgium, Netherlands, Germany, no matter where, Sweden, and North Africa, to fight on the ground with their own passports.

We heard from Michael Weiss yesterday, who's written a lot about ISIS, written one of the most definitive books. He says this nonsense we're putting on television, they're burning their passports -- no, they're not -- they're keeping their passports so they can come in with those passports and slip in, not even slip in, come back home with a passport.

GORANI: And, Christiane and Chris, also, this attacker, some of the attackers in "Charlie Hebdo" -- in the case of "Charlie Hebdo" never travelled to Syria. You don't need to go to Syria to receive weapons training on how to learn how to shoot an AK-47.

CUOMO: And these explosives that was used in these vests.

GORANI: You're radicalized online.

CUOMO: Not sophisticated and could have been locally learned and made.

AMANPOUR: Well, actually, could have been, but yesterday, the prosecutor was saying they probably got training on that abroad. It was a very sophisticated group, and this dovetails with what the French president says, this is an attack -- a war declared on France by an army of jihadists, used very specific words, an army of jihadists and terrorists, this attack was planned abroad, committed here with local accomplices. That's what we're seeing.

GORANI: Just to remind our viewers of the news the Belgium foreign minister gave us minutes ago five arrests were made in Brussels and that he is, quote, "quite sure these individuals are connected with the Paris attacks that took place on Friday." So, it goes beyond France.

CUOMO: There's no question that this has opened people's eyes to a reality that we should be familiar with but keeps on changing in shape, not just here in France but the world over with the G20 summit happening. There's pressure on President Obama to do different things as well.

[08:15:00] After the break we will talk about that. We'll have Christiane Amanpour, Hala Gorani, and me, Chris Cuomo. Please stay with us.

(COMMERCIAL BREAK)

CUOMO: Welcome back to CNN's continuing coverage of what happened in Paris, Chris Cuomo, Hala Gorani.

GORANI: All right. CNN has learned from a member of the French senate some new details on the investigation, that the first suicide bomber -- and we're talking about the attack on the soccer stadium -- that man who blew himself outside the stadium came to Europe as part of a highly organized group carrying a Syrian passport and smuggled in with refugees who landed on the group island of Leros about a month ago.

It raises, Chris, about refuge crime many questions about this influx of refugees fleeing violence and war in their home lands and coming to Europe to find safe haven. What kind of reaction will ordinary Europeans have to that information?

CUOMO: Well, policy has been developed to deal with the desperation and suffering, which is undeniable going on in Syria specifically, but also areas of the Middle East.

[08:20:02] People are fleeing for their lives from North Africa as well -- children and families are being devastated.

But this is now going to ignite a new fear in the United States and certainly playing out in the election.

Let's get to Chris Frates out of Washington, D.C. -- with a report on the political implications of this news, Chris, when American politicians running for president hear one of these killers had a false passport from Syria and that's how he got in, as an alleged refugee, it's going to bring harsh, harsh criticism.

CHRIS FRATES, CNN CORRESPONDENT: You're absolutely right about that, Chris. And we're seeing those developments play out on the campaign trail already where President Obama's plan to bring in at least 10,000 refugees is under attack from the Republicans running to take his job.

Donald Trump called the plan "insane". And former Governor Mike Huckabee said, "Taking in refugees is the craziest thing the country can do."

Meanwhile, Louisiana governor and presidential candidate, Bobby Jindal, sent a letter to President Obama yesterday demanding more information about the Syrian refugees that have started arriving in his home state. He wrote, quote, "It is irresponsible and severely disconcerting to place individuals who may have ties to ISIS in a state without the state's knowledge or involvement."

Now, GOP candidate, Rick Santorum, even arguing accepting refugees is exactly what ISIS wants the U.S. to do. Here's what he and his fellow candidate, Rand Paul, had to say.

(BEGIN VIDEO CLIP)

RICK SANTORUM (R), PRESIDENTIAL CANDIDATE: We accomplish what ISIS wants to accomplish. We accomplish what Assad wants to accomplish by accepting people they don't, most of them I would assume, they don't want to be in their geographic area. Whether they're Christians or whether they're Muslims who don't agree with them or whether they're folks who are not supportive of the Assad regime, whatever the case may be, by accepting them, we then displace them and now ISIS is stronger.

SEN. RAND PAUL (R-KY), PRESIDENTIAL CANDIDATE: I wouldn't invite Syrian refugees here. I will -- I will oppose them coming.

(END VIDEO CLIP)

FRATES: So, Democrats meanwhile said during their debate Saturday night that the U.S. should accept Syrian refugees, Hillary Clinton and Martin O'Malley said the country should take in as many as 65,000 refugees, while Bernie Sanders says there's no magic number but he was supportive of the idea.

Chris, Hala, back to you guys in Paris.

GORANI: All right. Chris Frates, thanks very much.

Joining us now for more is CNN terrorism analyst Paul Cruickshank with new information on what unfolded overnight in Brussels, and also, Lieutenant Colonel Robert Maginnis.

Paul, let's start with you.

PAUL CRUICKSHANK, CNN TERRORISM ANALYST: You just had the Belgian foreign minister on. He was telling you there were five arrests in Molenbeek, this district in north of Brussels and saying the reasons they were connected to the attack in Paris.

I've just been talking to a senior Belgian counter-terrorism official, he says that this group arrested in Brussels were in communication, were in contact with the Paris attackers. So, a confirmation of this link between Belgium, between France, and attacks in Paris. They did not find explosions on these people in these people in Brussels and may be the logistical step of supporting what happened in Paris.

CUOMO: Let's take one step back. We're going to have to talk about what this threat means in terms of the response. We have Maginnis with us for that.

But let's about what this threat is. It's something that Hala and I have been talking about when we're not on air. Islam versus Islamism -- the faith many people want to name mistakenly this perversion of the faith ISIS has indoctrinated in the notion of a state and what these people who exploded themselves came in the name of in all likelihood. Explain the distinction.

CRUICKSHANK: Well, the vast majority of Muslims hate ISIS and view it as a perversion of the religion. But ISIS themselves think their interpretation of the religion is the only acceptable interpretation of the religion.

CUOMO: What's the difference between Islam and Islamism?

CRUICKSHANK: Well, Islam is a religion and Islamism is a political movement.

GORANI: Which is not always violent. I think if you have --

(CROSSTALK)

CRUICKSHANK: Of course, there are lots of different types of Islamism, more moderate, perhaps the Islam Brotherhood and much more extreme, and so there are lots of different shades of this. But these ISIS suicide bombers, these ISIS fighters who came to Paris to launch these attacks -- they are religiously motivated. They believe they're going paradise. That's the key part of the motivation and why we saw them blow themselves up. That's exactly what they wanted to see happen and this has been very powerful for all these recruits going to Syria and Iraq.

[08:25:00] CUOMO: It raises the questions of -- words matter, language matters, and politicians parse all the time in terms of what the threat is, what the reaction is, what they'll do strategically. But part of the reality is what you call this and what you say about it, because you're fighting an ideology, as much as you are any man or woman on the ground in the name of this violence. How important is that moving forward from this?

CRUICKSHANK: Well, obviously, words matter a great deal. But I think the most important thing, moving forward for the entire international community, the entire Western world is put an end to this terrorist safe haven in Syria and Iraq. I mean, we learned from 9/11 if you have a terrorist safe haven, terrible things happen and we saw it in 9/11 and that safe haven in Afghanistan.

There's an even bigger safe haven in Syria and Iraq, a frightening number of Westerners there and now the possibility they're managing to send Middle Easterners from the region back here to launch attacks, expanding the number of possible people they have to launch these atrocities, Chris.

GORANI: And Lieutenant Colonel Maginnis, we've had aerial strikes on ISIS targets in Syria and Iraq for well over a year and a half now. Many countries have joined in on the effort -- even Turkey although they probably bombed Kurdish militant targets more than they do ISIS. But so far, it has done nothing but prevent huge gains in territory. So, it's not -- I mean, it is not working.

So, what needs to be done military?

LT. COLONEL ROBERT MAGINNIS (RET.), U.S. ARMY: I think this morning, that President Obama met with President Erdogan there in Turkey at the G20. They discussed an issue Erdogan has been pushing for a long time. I think we're ready for it.

That is a no-fly zone, an ISIS-free zone in the border area with Syria. That would allow refugees to move in there, safe from the carnage that's going on elsewhere in Syria and, of course, the Turks would help, we would help and parts of the coalition would help defend that.

That would stem the flow to a certain degree of many of the refugees trying to get out of Iraq and Syria. It's a start.

Of course, I think the president, when he met with his national security council yesterday probably said we really need to assess some of what we're doing.

Now, we have announcements in the last couple of days we're going to pick up the number of airstrikes against Syrians and Iraq or ISIS in Iraq. So it would appear as if the president is gradually shifting his policies of containment to something more aggressive, given what's happened in Paris and, of course, given perhaps what is happening -- that Russian airliner a week ago.

CUOMO: Well, Colonel, give us a fresh take on what exactly the situation is. Hala certainly has justifiable basis to say it hasn't worked. We see expansion of influence if not of territory, but we just heard President Obama say there has been containment within Syria and ISIS doesn't have the stronghold there they did have. You get different opinions.

What do you believe the reality is on the ground in Syria right now?

MAGINNIS: Well, Chris, of course, geographically, perhaps the footprint of ISIS in Syria and Iraq hasn't radically expanded. However, we have seen it more to franchise. You know, just the other day we bombed or the French bombed against an ISIS facility in Libya. We have seen it in the Stans. We have seen it in Afghanistan.

We have seen what you've been talking about the last few minutes is perhaps many ISIS trained people in Kalashnikovs and suicide bombers have come in with the flow of refugees and as a result, they have planted these people ready for somebody maybe al Baghdadi to pull the trigger and mass chaos like we've seen in Paris. Now, that's real threat.

And, of course, it was just what, a week ago we've heard in a couple of British papers that, in fact, was the strategy to infiltrate the refugees. The new revelation you have about the Syrian passport, I will tell you a month ago, the police in Stuttgart, Germany, arrested what they believe was an ISIS recruiter who had a suitcase full of Syrian passports.

CUOMO: All right. Colonel Maginnis, thank you very much and for the perspective on that.

GORANI: And I want to add something on this no-fly zone, the safe zone, whatever you want to call in northern Syria, the Turks have been pushing for it a long time. The Americans have not wanted it and said repeatedly in the past the conditions are not on the table. This is a military operation, it would need support from the air, you would need some to secure that zone, with who?

Rebel fighters say the Free Syrian Army, who else would do it? There is criticism directed at Turkey that the reason they do want this safe zone is to keep Kurdish militants out of it much more for that reason and much less to keep ISIS out of the zone and allow Syrian civilians to be safe there. So, it is a very political question and I'm sure it's being discussed yet today.